John Isner, of the US, returns the ball to Brazil's Thomas Bellucci during their match at the Rome Masters tennis tournament, in Rome, Wednesday, April 28, 2010. Bellucci won 7-6(7), 7-5. (AP Photo/Gregorio Borgia)

/ AP

John Isner, of the US, returns the ball to Brazil's Thomas Bellucci during their match at the Rome Masters tennis tournament, in Rome, Wednesday, April 28, 2010. Bellucci won 7-6(7), 7-5. (AP Photo/Gregorio Borgia)

John Isner, of the US, returns the ball to Brazil's Thomas Bellucci during their match at the Rome Masters tennis tournament, in Rome, Wednesday, April 28, 2010. Bellucci won 7-6(7), 7-5. (AP Photo/Gregorio Borgia) (/ AP)

John Isner, of the US, serves the ball to Brazil's Thomas Bellucci during their match at the Rome Masters tennis tournament, in Rome, Wednesday, April 28, 2010. Bellucci won 7-6(7), 7-5. (AP Photo/Gregorio Borgia)

/ AP

John Isner, of the US, serves the ball to Brazil's Thomas Bellucci during their match at the Rome Masters tennis tournament, in Rome, Wednesday, April 28, 2010. Bellucci won 7-6(7), 7-5. (AP Photo/Gregorio Borgia)

John Isner, of the US, serves the ball to Brazil's Thomas Bellucci during their match at the Rome Masters tennis tournament, in Rome, Wednesday, April 28, 2010. Bellucci won 7-6(7), 7-5. (AP Photo/Gregorio Borgia) (/ AP)

John Isner, of the US, returns the ball to Brazil's Thomas Bellucci during their match at the Rome Masters tennis tournament, in Rome, Wednesday, April 28, 2010. Bellucci won 7-6(7), 7-5. (AP Photo/Gregorio Borgia)

/ AP

John Isner, of the US, returns the ball to Brazil's Thomas Bellucci during their match at the Rome Masters tennis tournament, in Rome, Wednesday, April 28, 2010. Bellucci won 7-6(7), 7-5. (AP Photo/Gregorio Borgia)

John Isner, of the US, returns the ball to Brazil's Thomas Bellucci during their match at the Rome Masters tennis tournament, in Rome, Wednesday, April 28, 2010. Bellucci won 7-6(7), 7-5. (AP Photo/Gregorio Borgia) (/ AP)

John Isner, of the US, left, greets, Brazil's Thomas Bellucci at the end of their match at the Rome Masters tennis tournament, in Rome, Wednesday, April 28, 2010. Bellucci won 7-6(7) 7-5. (AP Photo/Gregorio Borgia)

/ AP

John Isner, of the US, left, greets, Brazil's Thomas Bellucci at the end of their match at the Rome Masters tennis tournament, in Rome, Wednesday, April 28, 2010. Bellucci won 7-6(7) 7-5. (AP Photo/Gregorio Borgia)

John Isner, of the US, left, greets, Brazil's Thomas Bellucci at the end of their match at the Rome Masters tennis tournament, in Rome, Wednesday, April 28, 2010. Bellucci won 7-6(7) 7-5. (AP Photo/Gregorio Borgia) (/ AP)

John Isner, of the United States, serves the ball to Brazil's Thomas Bellucci during their match at the Rome Masters tennis tournament, in Rome, Wednesday, April 28, 2010. Bellucci won 7-6(7), 7-5. (AP Photo/Gregorio Borgia)

/ AP

John Isner, of the United States, serves the ball to Brazil's Thomas Bellucci during their match at the Rome Masters tennis tournament, in Rome, Wednesday, April 28, 2010. Bellucci won 7-6(7), 7-5. (AP Photo/Gregorio Borgia)

John Isner, of the United States, serves the ball to Brazil's Thomas Bellucci during their match at the Rome Masters tennis tournament, in Rome, Wednesday, April 28, 2010. Bellucci won 7-6(7), 7-5. (AP Photo/Gregorio Borgia) (/ AP)

After withdrawing from last week's Barcelona Open, Nadal appeared fresh and dictated play with his usual combination of heavy topspin, few unforced errors and baseline winners. The third-ranked Spaniard improved to 6-0 in his career against his 29th-ranked German opponent.

"It wasn't my best match, but I did well," Nadal said. "I played safe and I played focused all the time. Philipp made more mistakes than usual."

Nadal has won the clay-court tournament four of the past five years and is the favorite again after top-ranked Roger Federer was stunned by Ernests Gulbis on Tuesday.

Federer got some consolation Wednesday when he teamed in doubles with fellow Swiss player Yves Allegro to beat sixth-seeded Simon Aspelin of Sweden and Paul Hanley of Australia 4-6, 6-3, 10-8 after a champions tiebreaker.

Nadal only faced one break point in his match - at 2-3 in the second set - and saved it when Kohlschreiber missed an easy backhand wide. Nadal broke in the next game, producing a high passing shot that Kohlschreiber could barely get his racket on, and cruised the rest of the way.

The new 10,500-seat stadium at the Foro Italico was nearly full for the match, but Nadal gave the spectators only 1 hour, 10 minutes of play. He led 18-15 in winners and committed only 11 unforced errors to Kohlschreiber's 28.

Nadal's dominance was similar to when he won the Monte Carlo Masters two weeks ago, dropping only 14 games in five matches and routing Fernando Verdasco 6-0, 6-1 in the final.

With Nadal absent, Verdasco won his fifth career title in Barcelona last week. He edged Simone Bolelli 7-6 (11), 6-3 to open his campaign in Rome.

Fifth-seeded Robin Soderling extended his solid form with a 6-1, 7-5 win over Paolo Lorenzi.

Soderling was coming off a runner-up finish at the Barcelona Open, where he lost to Fernando Verdasco in three sets. In the Swede's previous two tournaments - Masters Series events in Indian Wells and Key Biscayne - he reached the semifinals.

Soderling ended Nadal's perfect record at the French Open last year and is in the same quarter of the draw as the Spaniard.